Sheet-stretching machine



Feb. 25, 1930 'T. H. HEACOCK 11m. 1,748,603

SHEET STRETCHING MACHINE Filed May 18, 1928 2 Sheets-Sheet LLU I l INXZ'EHTR.

Jim iz/ -x/zr' W l -f Feb. 25, 1930. T. H. HEACOCK 4 INY'ENIIEIR.

Patented Feb. 25, 1930 UNITED STATES PA'I'EN'T' OFFICE THOMAS E. HEAOOOK, OF CANTON, AND PAUL LARSON, OF LOUISVILLE, OHIO SHEET-STRETCHING MACHINE Application filed May 18, 1928. Serial No. 278,775.

This invention has reference to metal stretching machines adapted particularly for the stretching, leveling and shaping of preferably metal sheets.

- In the manufacture of metal sheets, it is well known to those engaged in the practice, that said sheets on leaving the rolls are more or less warped or buckled and irregular in thickness by reason thereof, or otherwise affected by kinks, sometimes covering the entire surface of the sheet which in such condition, can not be well packedor bundled for shipping as the warped and irregular surfaces prevent them lying evenly and smoothly and making them unfit for commercial use. It is to the elimination of these irregularities and defects in the sheets that this invention has reference and it has for its principal ob- 1' eat the provision of a new and improved sheet 2 clamping jaw assembly including upper and lower jaw clamping members, one of such jaw members of the assembly comprising a multiplicity ofindividual independently adjustable jaw clamping units or members whereby upon the insertion of an irregularly formed sheet or series of superimposed sheets between said jaw clamping assembly, said jaw member provided with a multiplicity of independently adjusted jaw units will conform and adjust themselves to the irregularities in the surface of the sheet, thereb clamping upon the sheet or sheets throug out the length of the jaw member and preventin any chance or possibility of the sheet or s eets slipping from the jaw assembly causin' further kinking and crimping when eing stretched and leveled. The invention has for a further object to provlde in a clamping jaw assembly, complementary upper and lower jaw clamping members, one of said members comprising a plurality of juxta ositioned jaw clam mg umts, each unit in ep'endently adjustablle to the other. when said members are operated to clamping position upon a sheet or sheets.

Heretofore, in machines of this character, I

considerable delay and loss of material has had to be contended with due to the slipping of the sheet or sheets inserted between the jaw members when being stretched and leveled .upper and lower jaw clam ing members and due to the jaw members being incapable of conforming to the iregularities in said sheet orsheets, necessitating filing of the sheet clamping surfaces of the jaw members and in some cases even shimming the jaw members throughout their length in order to accommodate the swells, bulges and uneven surfaces in said. sheets, all these manipulations, delays and loss of material being eliminated in this machine, to be hereinafter described.

That the invention may be more fully understood, reference may be had to the accompanying drawings forming a part of this description and illustrating a preferred embodimentof the invention, in which Fig. 1 is a top plan view, broken away, showmg'the general arrangement of our implfoved sheet stretching and leveling ma- 0 me;

Fig. 2 is a side view in elevation of Fig. 1; Fig. '3 is an end view in elevation of one of the aw clamping assemblies,"showing the lever and gear connections for actuating the a art of the supporting rame therefor; 5

. ig. 4 is a side view, broken away, of vone of the jaw clamping assemblies, showing the arrangement of the upper and lower jaw members, the latter. including a multiplicity of individual independently adjustable jaw clamping units or members, and the lever and gear connections for actuating said upper and lower jaw members; v

Fig. 5 is a sectional view of a jaw clamping assembly, as the same would appear if taken on the line 4-4, Fig. 4, the jaw members shown in sheet receiving position and a sheet being shown in dotted lines;

Fig. 6 is a view similar to Fig. 5 showing the jaw members in closed or clamping position upon a sheet shown in dotted lines;

Fig. 7 is a detail view of the upper and lower jaw members showing the introduction of a plurality of superimposed sheets between the opened members; I

Fig. 8 is a view similar to Fig. 7 showing I the jaw members in clamped position upon the sheets, and

" Fig. 9 is an enlarged prospective view of one of the independently adjustable jaw units or members showing its connection to an operative shaft and its milled sheet engaging clamp portion.

Like characters of reference denote corresponding parts throughout the figures.

Reference being had to Figs. 1 and 2 of the drawings, our improved sheet stretching and leveling machine includes a reetangularly shaped frame having sides 1 and 2 and ends 3 and 4, which may be of any suitable size for the sheets or material to be treated therein. Adjustably and slidably associated with the end 3 is a bar or rod 5 which has a threaded connection through and with ascrew assembly 6 which is provided with a plurality of spokes or hand holds 7 which upon being rotated, will be understood to screw the bar or rod 5 backwards or forwards to any adjusted position as may be required. The screw end of the bar or rod 5 is suitably bolted to a roller support 8 and to reduce friction a tsack or other suitable foundation 9 may be provided for the support to ride upon. The sheet end of the bar or rod 5 is suitably connected within the frame to preferably mediate the length of a jaw supporting casting member or housing 10, the ends of which are adapted to slidably ride upon the top sides 11 and 12 of the frame members 1 and 2.

Slidably associated with the end 4 is a power actuated rod or plunger 13 which is disposed through a power mechanism, such as a hydrostatic pump, including a water pump 14, a pulley 15, suitable water pipe connections 16 and a cylinder 17, the rotation of the pulley 15 by means of a belt, not shown, pumping and forcing water into the cylinder 17 by means of the pipe connections 16, will be understood to cause the rod or plunger 13 to move slowly but with great force. The power end of the rod or plunger 13 is provided with a stop member 18. The sheet end of the rod or plunger 13 is similarly connected within the frame to a similarly constructed jaw supporting casting member or housing 19, the ends of said casting or housing supported to slide on rests 20 and 21 provided on the top face of the frame members 1 and 2, as is the casting or housing 10 on the rests 11 and 12. A coiled spring 22 is provided on the rod or plunger 13 between the casting or housing 19 and the end wall 4 for the purpose of moving back or returning the plunger 13 and casting member or housing 19 when the hydrostatic pump has been shut off in order that the material worked upon, such as a sheetor sheets, may be removed from the jaws in the housing members 10 and 19, which will be hereinafter described.

The housings 10 and 19 previously'referred to, see Figs. 1 and 2, it will be observed, are substantially alike in construction and funct on, and for purposes of further illustration and description, reference will be only had to the description of the housing 10 and its associated parts, see Figs. 3 to 9 both inelusive.

Reference being had to Fig. 4, the housing 10 is provided with a semi-tubular groove or opening 23 disposed approximately longitudinally its length and medially thereof in which are disposed parallel upper and lower complementary acting material gripping jaw members 24 and 25 respectively, said members carried by shafts 26 and 27, respectively, being journaled in the ends of said housing, the shaft ends at one end of the housing being provided with meshed gears 28 and 29, see Figs. 3 and 4, the former provided with a manually operable lever arm 30, which when actuated will be understood to rock the shafts '26 and 27, and with them the complementary acting material gripping jaw members 24 and 25. The upper jaw member 24 is of the usual and well known type, being constructed in one entire piece or unit, the clamping or material engaging surface of the member being milled for the purpose of gripping and clamping upon the material to be worked upon.

The lower jaw clamping or gripping member 25 comprises a plurality of individual members or jaw clamping units 25 disposed in juxtaposition with each other, see Fig. 4, each member 25, see Fig. 9, being loosely keyed as at 31 to the shaft 27 for the purpose of allowing limited annular movement thereof whereby the'j aw units or members 25 may accommodate themselves independently of each other to material, such as a sheet or sheets having irregular surfaces and thicknesses. The members 25 like the member 24 are provided with a milled gripping surface for the purpose of gripping and clamping upon the material to be worked-upon.

Reference being had to Figs. 5 and 6, the former shows the introduction of a single sheetof material into and between the opened complementary acting upper and lower jaw members 24 and 25, the latter figure illustrating the raised lever arm 30 which results in the closing of the jaw members 24 and 25 into clamped or closed position upon a sheet of material. Figs. 7 and 8 are similar views except that a plurality of superimposed sheets are shown inserted between the opened and closed or clamped jaw members 24 and 25.

In the operation of this machine, it will be understood that the casting or housing member 10 is first adjusted to its fixed sta-.

tionary position which is determined by the size of the material, such as a sheet or sheets to be leveled and stretched, such adjustment being accomplished by the rotation of the screw 6 which causes the bar or rod 5 to move toward or away from the casting or housing 19, as may be desired.

Having set the housings 10 and 19 in their respective operative positions from each other, the complementary jaw members in each housing are set in material receiving tion by means of the manually operated lever;

arm 30, see Figs. 6 and 8. The material is now ready to be stretched and leveled and is accomplished by the operation ofthe hydrostatic pump which causes the plunger 13 to be forcibly pulled or withdrawn away from the fixed or stationary housing 10 very slow ly but forcibly, resulting in the material clamped between the jaw members 24 and 25 in each housing to be stretched and leveled and removin all presence of bulges, kinks and other de ects in the material. The pump is then shut off and the plunger 13 is returned to its original position by means of the coil spring 22 enabling the jaw members 24 and 25 to be opened and the material clamped therebetween to be released and removed.

It will a pear obvious that upon the insertion and c amping of material of the character just referred to between the jaw members of the housings 10 and 19, that the individual jaw members or units 25 comprising the lower member 25 will individually and independently of each other adjust and accommodate themselves to the irregular surfaces and thicknesses of the material thereby eliminating any possibility of the material slipping between the jaw members of the housings during the stretchin and leveling period, thereby preventing rther distortiomof the material.

' For purposes of illustration and disclosure, we have shown the individual and independently adjustable members 25" arranged in juxtaposition with each other having identical longitudinal dimensions of the other. It is apparent that the members 25' may be of unequal longitudinal dimension and arranged'in other sequence, as the demands may require.

What we claim is 1. In a machine for stretching metallic sheets, the combination of a pair of oscillat-.

able jaws adapted to coact in the gripping of opposite sides of sheet material, one of said jaws comprising a plurality of individual members in juxtaposition with each other, and means for movin the jaws in unison.

2. In a machine or stretchin metallic sheets, the combination of a pair of oscillatable jaws adapted to' coact 1n the gripping of opposite sides of sheet material, one of said jaws comprising a plurality of individual members in juxtaposition with eachother, and each member adapted for independent movement in relation to the other members whereby the jaws will accommodate themselves to material having irregular surfaces and thicknesses. v

terial, one of said jaws comprising a plu- I rality of individual members in juxtaposition with each other.

4. In a machine for stretching metallic sheets, the combination of a pair of parallel spaced shafts, means to rock said shafts in unison, acting material gripping jaws car- ,ried by each shaft adapted to coact inthe gripping of opposite sides of the sheet materlal, one of said jaws comprising a plurality of individual members in juxtaposition with each other, and each member adapted for independent movement on its shaft in relation to the other members whereby the jaws'will accommodate themselves to material having irregular surfaces and thicknesses.

5. In a machine for stretching metallic sheets, the combination of a housin a pair of parallel spaced shafts journale in' said housing, means to rock said shafts in unison, and material gripping jaws carried by each shaft adapted to coact in the gripping of opposite sides of the sheet material one of said jaws comprising a plurality of individual members in juxtaposition with each other.

6. Ina machine .for stretching metallic sheets, the combination of a housin a pair of parallel spaced shafts journale in said housing, means to rock said shafts in unison, material gripping jaws carried by each shaft adapted to coact in the gripping of opposite sides of the sheet material, one of said jaws comprising a plurality of individual mem-.

bers in juxtaposition with each other, and

each member adapted for independent adapted to coact in the gripping of o posite. sides of the sheet material, the jaws 0 one of each of said airs of shafts com rising a plurality of individual members in uxtaposition with each other. 8. In a machine for stretching metallic sheets, the combination of a frame, a pair of housings adapted for movement toward and from each other, pairs of parallel spaced shafts journaled in each housing, means to rock each pair of shafts in unison, material gripping jaws carried by each pair of shafts adapted to coact in the gripping of o posite sides of the sheet material, the jaws 0 one of each of said pairs of shafts comprising a plurality of individual members in 'uxtaposition with each other, and each mem er adapted for independent movement on its shaft inrelation to the other members whereby the respective pairs of jaws will accommodate themselves to material having irregular surfaces and thicknesses.

9. In a machine for stretching metallic sheets, the combination of a pair of parallel spaced shafts, means to rock said shafts in unison, material gripping jaws carried by each shaft ada ted to coact in the gripping of opposite sides of the sheet material, one of said jaws comprising a plurality of individual members in juxtaposition with each other, each member being keyed to its shaft in a manner to allow limited annular movement thereof whereby the said members may accommodate themselves to material having irregular surfaces and thicknesses.

In witness whereof,,we have hereunto affixed our hands this 16 day of May, 1928.

THOS H. HEACOCK. PAUL LARSON. 

